import Data.Semigroup
import Data.Monoid
import qualified Control.Arrow         as Arrow
import qualified Data.Vector.Unboxed   as VU
import qualified Data.ByteString.Char8 as BSC8
-- https://blog.miz-ar.info/2019/01/fast-fibonacci/
data FibPair a = FibPair !a !a
  deriving (Eq, Show)

instance (Num a) => Semigroup (FibPair a) where
  FibPair a b <> FibPair a' b'
    = FibPair (a * b' + (b - a) * a') (a * a' + b * b')
  stimes = stimesMonoid

instance (Num a) => Monoid (FibPair a) where
  mempty = FibPair 0 1

fibOne :: (Num a) => FibPair a
fibOne = FibPair 1 1

fibPair :: Int -> FibPair Integer
fibPair i = stimesMonoid i fibOne

fastDoubling :: Int -> Integer -> (Integer, Integer)
fastDoubling 0 mo = (0, 1)
fastDoubling 1 mo = (1, 1)
fastDoubling i mo
  = let (a, b) = fastDoubling (i `quot` 2) mo
    in if even i
       then (a * (2 * b - a) `mod` mo, (a * a + b * b) `mod` mo)
       else ((a * a + b * b) `mod` mo, b * (2 * a + b) `mod` mo)

fib :: Int -> Integer -> Integer
fib i mo = case fastDoubling (i - 1) mo of
          (a, _) -> a

main :: IO ()
main = do
  (n, mo) <- parse2
  print $ fib n (fromIntegral mo)

type Parser a = BSC8.ByteString -> Maybe (a, BSC8.ByteString)
parseInt :: Parser Int
parseInt = fmap (Arrow.second BSC8.tail) . BSC8.readInt
parse2 :: IO (Int, Int)
parse2 = (\vec -> (vec VU.! 0, vec VU.! 1)) . VU.unfoldrN 2 parseInt <$> BSC8.getLine